Method of making slide fastener stringers



Jan. 6, 1970 E. E. CUCKSON ET AL 3,487,531

METHOD OF MAKING SLIDE I-ASTENER STRINGERS Filed Nov. 196T 3 Sheets-Sheet INVENTORS Arthur L Jones a Eric Cucks on BY ATTOR EY m 6, 1 E. E. CUCKSON ET 3,437,531

METHOD OF MAKING SLIDE FASTENER STRINGERS Filed Nov. 1967 v 5 Sheets-Sheet 2 ll 4 Q 11 m 50 a:

. INVENTORS Arthur L. Jones 0.

Eric E. Cuch'son Y Wk ATTOR Y 1970 E. E. CUCKSON E AL 3,487,531

METHUD OF MAKING SLIDE FASTENEIR STRINGERS 3 Sheets-Sheet Filed Nov. J, 1967 INVENTORS Arthur L.Jones Em E. C ckson BY b ATTORN United States Patent 3,487,531 METHOD OF MAKING SLIDE FASTENER STRINGERS Eric Engel Cuckson, Penrith, New South Wales, and Arthur Llewelyn Jones, Glenbrook, New South Wales, Australia, assignors to Scovill Manufacturing Company, Waterbury, Conn., a corporation of Connecticut Filed Nov. 9, 1967, Ser. No. 681,846 Int. Cl. B21d 53/52; B21f 45/18; B29d /00 US. Cl. 29-410 9 Claims ABSTRACT OF THE DISCLOSURE A slide fastener is produced by weaving a preformed strip of flexibly connected, spaced apart fastener elements into a tape; wherein the strip is bent at a sharp angle and the individual fastener elements in turn, are projected into a shed of warp threads in such a manner that when the shed is closed, one or more of the warp threads are looped across each fastener element and drawn tight in this position where they are locked in place by the weft when inserted.

This invention relates to a method of making slide fastener stringers and more particularly to an improved method of weaving a preformed strip of flexibly connected, spaced apart fastener elements into the edge of a textile tape.

In the past, such fastener element strips have been woven in place by weft threads extending around the strips between the elements. To provide the required strength, such weft threads must be stronger and thus more expensive than would otherwise be employed.

In a general way the invention is a method for producing a slide fastener stringer having fastener elements, comprising weaving a textile ribbon, inserting the elements in turn into individual sheds formed during weaving of the ribbon, and changing each shed while the respective element is projecting therein to bind the element into position with one or more warp threads.

A preferred embodiment will now be described in which a stringer according to the invention consists of a textile tape of any convenient construction but preferably one woven upon a loom of the kind described in US. 2,891,583 dated June 23, 1959. This loom is shuttleless and does not employ a beating-up comb, achieving the same effect by an increased angle of the sheds. The fastener elements for the stringer may be of any prior type whether metal or thermoplastic, separated, or extruded or moulded in strip form. Preferably, however, the elements are extruded in a ladder-like strip of the kind described in our copending application Ser. No. 582,918 filed Sept. 29, 1966, now Patent No. 3,414,948, issued Dec. 10, 1968.

The fastener elements in each instance can be considered each as possessing a head portion for engagement with the coacting elements on the opposite stringer, a base portion remote from the head and a stem interconnecting the head and base portions. The same portions effectively exist in the conventional spiral type structure which is included in this description within the category of preformed strip. In the case of strip forms the individual fas ener elements are interconnected by a web portion. The web in the ladder-like strip referred to above is of textile yarn which has particular advantages when applied to the production of stringers to be described hereafter.

In-the weaving of the tape. one or a plurality of warp threads are on a shed movement which can be 3-1, 22 or in such suitable numbers corresponding to the ratio of thickness of fastener elements to the number of picks. Each fastener element is inserted into a respective shed "ice prior to the closing thereof in such a manner that when the shed is closed one or more of the warp threads of the shed are looped over the stem portion of the element, are drawn tight in this position and locked in place by the weft when inserted.

As above mentioned, the ladder-like element strip has advantages in this application and these are obtained due to the flexibility of the strip which permits each element to be bent sharply with respect to the strip, even to an angle approaching The one or more warp threads used to bind the fastener elements may be set in from the edge of the tape slightly so that the tape edge will cover the fastener, and this is an advantage over previous methods of weaving slide fastener stringers where special covering means had to be employed.

Other objects and advantages of the invention will hereinafter more fully appear. In the accompanying drawings I have shown for purposes of illustration, one embodiment which the invention may assume in practice.

In these drawings:

FIG. 1 is a plan view of a piece of slide fastener stringer made in accordance with our invention;

FIG. 2 is a cross section through the slide fastener stringer;

FIG. 3 is a longitudinal section along line 3-3 of FIG. 1;

FIG. 4 is a fragmentary plan view of the stringer as it is being woven and showing the weft inserting finger;

FIG. 5 is a detail plan view on an enlarged scale showing a fastener element projected into a shed;

FIG. 6 is a view similar to FIG. 5 showing a succeeding step in the weaving operation; and

FIG. 7 is a diagrammatic view showing the handling of the warp threads.

The fastener elements in the kind of strip shown in the drawings, each consists of a thermoplastic piece bent to U-shape having a head portion 10 of any suitable form adapted to interlock with mating elements of a companion stringer; and a pair of base portions 11 and 12 connected to the head 10 by stem portions 13 and 14, respectively. Preferably each stem portion has an intermediate enlargement 15 so as to provide in effect, a transverse groove 16 around each stem portion. Athough there is an open space 17 adjacent the head 10, the base portions may come close together or even contact one another. The fastener elements are spaced apart in the finished fastener as indicated in FIG. 1, and are flexibly connected by small textile cords 18 and 19 extending through the base portions 11 and 12, respectively. As explained in our above mentioned application, the fastener elements are molded or extruded on the cords 18 and 19 in ladder-like form and then the elements are bent to U-shape to complete the preformed strip ready for the weaving process.

The weaving operation shown partially in FIG. 4 indicates a finished flat tape 20 moving out of the loom in the direction indicated by the arrow. The weft is inserted by a reciprocating needle 21 which catches a weft thread from a suitable threader while in the projected position shown in FIG. 4, then pulls a double pick across the tape while the eye 22 is closed by a reciprocating pin or bar 23. When the needle pulls through a previous weft loop 24, the needle eye opens to release the looped end of the drawn weft thread, and the needle returns through the now stationary loop and a new shed which has meanwhile been formed by crossing the warp threads. This results in a knit selvedge edge 25 as explained more fully in our above mentioned issued patent.

As indicated in FIG. 7, group 26 of warp threads is manipulated by heddles 27 and another group 28 by heddles 29 in the normal manner for producing a flat tape as explained in the patent above referred to. One important difference is that the finished tape feeds over a beam in a downward sloping direction in line with the upper group of warps 26.

To simplify the description, I have shown only one binding warp 31 manipulated by a special heddle 32 but it will be understood that a pair or even more of such warps may be employed and manipulated by heddles which operate in phase or 180 from one another. In View of the fact that in the shed position shown in FIG. 7 it is desired to hold the binding warp 31 at a substantial angle to the warps 26 and preferably at a right angle, a special mechanism is employed to manipulate this warp 31 in a semicircular path indicated by the dotted line 33. I have indicated the essential components of one type of mechanism for accomplishing this purpose. A link 34 can be reciprocated in any suitable manner from another portion of the loom to oscillate a lever 35 and gear 36 through a predetermined angle, for example, 45. Smaller gears 37 and 38 mesh with the larger gear 36 and are reciprocated through the desired angle of approximately 180. Parallel cranks or levers 39 and 40 are keyed to the same shafts as the gears 37 and 38 respectively and are of equal length. They are pivotally attached to the bar-life extension 41 of heddle 32 by pins 42 and 43. The two extreme positions of the heddle 32 and the levers 39 and 40 are shown in full and dotted lines in FIG. 7.

The fastener element strip is guided in any suitable manner from a continuous source of supply as by means of a tube 44, a portion of which is seen in FIG. 5. The strip approaches the weaving operation along the top surface of the tape in a direction opposite to that of the tape movement. A pusher bar 45 has imparted thereto a reciprocating motion in a direction parallel to the tape 25 by any suitable mechanism connected to another part of the loom. The bar 45 is preferably formed with a bevelled surface 46 and a rounded end portion 47 over which the base portions of the fastener elements move.

When the shed is formed as seen in FIGS. 5 and 7, the bar 45 moves inwardly toward the shed and the fastener element strip bends around the end 47 to project a single element designated E in FIG. 5, into the shed alongside the binding warp 31. During the approach of this element E to that position, a stop member 48, also having imparted to it a reciprocating movement in any suitable way, arrests the fastener element E for a very short period of time required for action of the weft laying needle 21, whereupon the stop 48 moves away allowing the element E to snap around to the position of element E. It will thus be seen that the fastener strip enters the loom with the elements at right angles to the tape in one direction, is bent sharply to project the individual elements in turn in the lengthwise direction of the tape, and finally each element turns again through 90 so that it extends away from the finished tape. This sharp bending action is permitted due to the highly flexible character of the connecting cords 18 and 19. It has also been found that the connecting portions between the individual fastener elements of a coil-type strip also have the required degree of flexibility to operate in a similar manner in our improved weaving process.

The parts are so positioned when the fastener element E is released from stop 48 that it will snap into the position of fastener element E with the binding warp 31 engaging in the groove 16 between stem portions 13 and 14 and the base portions 11 and 12. When the fastener element has advanced far enough, the heddle 32 moves in its semicircular path to form a loop 49 across the stern portion. In order to support the fastener element while this loop 49 is being drawn tightly into position, a reciprocating finger 50 is actuated in timed relation to the rest of the machine, so that its pointed end 51 moves into the crotch or space 17 in the fastener element and of course is withdrawn again at the proper time.

As seen in FIGS. 2 and 4, at least one and preferably two or more of the tape warps are located to the outside of the fastener binding warp 31 so as to form a protective edge 52 over the stern portions of the fastener elements. At each change of shed, the weft laying needle 21 inserts a double pick as indicated by the numeral 52 in FIG. 3. Alternate double picks are located between fastener elements to secure the loops 49 of the binding warp while the inbetween double picks 53 are located directly under the fastener elements.

We claim:

1. In a method of producing a slide fastener stringer with a preformed strip of flexibly connected, spaced apart fastener elements, the combination of the follow ing steps:

(a) weaving a textile tape;

(b) projecting the individual elements in turn into sheds as formed during the weaving of the tape; and

(c) changing the shed while a fastener element is projected therein to bind the element to the tape with one or more wrap threads.

2. In a method of producing a slide fastener stringer with a preformed strip of flexibly connected, spaced apart fastener elements, the combination of the following steps:

(a) forming a shed wherein most of the warp threads are tape warps at a normal angle suitable for producing a fiat tape, and wherein at least one fastener binding warp located adjacent to one edge of the tape extends outwardly at a wide angle to one side of said shed;

-(b) guiding the fastener element strip toward the shed along one side of the woven tape and in the direction opposite that of the advancing woven tape;

(0) projecting each of said elements in turn into a shed so that it is positioned outside said tape warps and alongside said binding warp;

(d) moving said projected element laterally while engaging said binding wrap;

(e) changing the shed by crossing said tape warps and shifting said binding warp to the oppisite side of the shed and thus across said fastener element; and

(f) inserting a weft thread at each change of shed to secure all of said wraps.

3. In the production of slide fastener stringers, the combination defined in claim 2 wherein each of said fastener elements extends transversely of the tape as it is guided toward the shed, and wherein the stringer is bent sharply so that when an element is projected into the shed, it extends in the lengthwise direction of the tape, and wherein such fastener element turns again at right angles to extend outwardly of the tape edge after a change of shed.

4. In the production of slide fastener stringers, the combination defined in claim 2 wherein said fastener binding warp is spaced from that one edge of the tape referred to in clause (a) of claim 2, by one or more tape warps.

5. In the production of slide fastener stringers, the combination according to claim 2 further characterized by the fact that the binding warp thread is moved in a curved path in a plane perpendicular to the tape while the tape warps are moved in a straight line path.

6. In the production of slide fastener stringers the combination according to claim 2 further characterized by the unique position of the warp threads when a fastener element is projected into the shed wherein one group of tape warps is in alignment with the woven tape, the other group of tape warps at a substantial angle on one side of the tape, and the fastener element binding warp is at a substantial angle to the opposite side of said tape.

7. The method according to claim 6 wherein said angle of the binding warp is at about to the plane of the tape.

'8. In the production of slide fastener stringers the combination defined in claim 2 wherein the feed of the tape 5 6 during weaving is continuous, characterized further by 2,463,840 3/1949 wint rhalter 29 41() larresting each of the fastener elements in turn after it is 2,744,313 5 195 b w 29-403 projected into its shed and during insertion of the weft. 2 91,5 3 1959 Jones 139 124,1 9. The method of producing slide fastener stringers 2,942 333 6/1960 Burbank g according to claim 2, further characterized by supporting 3 039,408 6/1962 408 X in a pOSifiVC manner 63.611 of 11116 fa ten dements dur g 5 3 414 94 12 196 c i z 24:205 13 that changing of the shed referred to in clause (e) of 1 mm 2 References Cited WAYNE A. MORSE, 111., Primary Examiner UNITED STATES PATENTS 10 1 R, 2,335,034 11/1943 Winterhalter 29--207.5 29-33.2, 207.5

2,395,869 3/1946 Hendley 29410 

